Safety regulations may require disconnecting and/or short-circuiting one or more photovoltaic (PV) generators or other components in case of an unsafe condition occurring in a photovoltaic installation. For example, safety regulations require that in case of an unsafe condition (e.g. a fire, a short-circuit, carrying out of maintenance work), the maximum voltage at any point in a photovoltaic installation may not exceed a safe voltage level. In some photovoltaic systems, it may be necessary to disconnect and/or short-circuit one or more photovoltaic generator(s) to achieve the safe voltage requirement. While photovoltaic systems may be deployed for tens of years, safety regulations may change at shorter time intervals (e.g. every several years). It would be advantageous to have a controllable safety switch which may be controlled to disconnect or short-circuit a PV generator in case of a safety hazard, and which may be controlled to reconnect the photovoltaic generator once the system is safe again. It would be desirable for controllable safety switches to be cost-effective and easily deployed.